Silvestri, Romano’s team published research in Journal of Medicinal Chemistry in 2008 | CAS: 866837-96-9

Ethyl 5-amino-1-phenyl-1H-pyrazole-3-carboxylate(cas: 866837-96-9) belongs to anime. To avoid the problem of multiple alkylation, methods have been devised for “blocking” substitution so that only one alkyl group is introduced. The Gabriel synthesis is one such method; it utilizes phthalimide, C6H4(CO)2NH, whose one acidic hydrogen atom has been removed upon the addition of a base such as KOH to form a salt.Name: Ethyl 5-amino-1-phenyl-1H-pyrazole-3-carboxylate

Name: Ethyl 5-amino-1-phenyl-1H-pyrazole-3-carboxylateOn March 27, 2008, Silvestri, Romano; Cascio, Maria Grazia; La Regina, Giuseppe; Piscitelli, Francesco; Lavecchia, Antonio; Brizzi, Antonella; Pasquini, Serena; Botta, Maurizio; Novellino, Ettore; Di Marzo, Vincenzo; Corelli, Federico published an article in Journal of Medicinal Chemistry. The article was 《Synthesis, cannabinoid receptor affinity, and molecular modeling studies of substituted 1-aryl-5-(1H-pyrrol-1-yl)-1H-pyrazole-3-carboxamides》. The article mentions the following:

The new 1-phenyl-5-(1H-pyrrol-1-yl)pyrazole-3-carboxamides were compared with the reference compounds AM251 and SR144528 for cannabinoid hCB1 and hCB2 receptor affinity. Compounds bearing 2,4-dichlorophenyl or 2,4-difluorophenyl groups at position 1 and 2,5-dimethylpyrrole moiety at position 5 of the pyrazole nucleus were generally more selective for hCB1. On the other hand, the N-cyclohexyl group at the 3-carboxamide was the determinant for the hCB2 selectivity, in particular when a 3,4-dichlorophenyl group was also present at position 1. Compound I was the most selective ligand for the hCB1 receptor (Ki (CB2)/Ki (CB1) = 140.7). Derivative II, the most potent hCB1 ligand (Ki = 5.6 nM), was equipotent to AM251 and behaved as an inverse agonist in the cAMP assay (EC50 ∼1 nM). The carbonyl oxygen of both I and II formed a H-bond with K3.28(192), while the substituents at the nitrogen fitted in a pocket formed by lipophilic residues. This H-bonding interaction was proposed to account for the high affinity for receptors’ inactive state and the inverse agonist activity. The experimental part of the paper was very detailed, including the reaction process of Ethyl 5-amino-1-phenyl-1H-pyrazole-3-carboxylate(cas: 866837-96-9Name: Ethyl 5-amino-1-phenyl-1H-pyrazole-3-carboxylate)

Ethyl 5-amino-1-phenyl-1H-pyrazole-3-carboxylate(cas: 866837-96-9) belongs to anime. To avoid the problem of multiple alkylation, methods have been devised for “blocking” substitution so that only one alkyl group is introduced. The Gabriel synthesis is one such method; it utilizes phthalimide, C6H4(CO)2NH, whose one acidic hydrogen atom has been removed upon the addition of a base such as KOH to form a salt.Name: Ethyl 5-amino-1-phenyl-1H-pyrazole-3-carboxylate

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics